This invention generally relates to job ordering systems for image-forming machines. More particularly, this invention relates job ordering systems for image-forming machines having one or more inserted sheets in a image-forming job.
Image-forming machines are used to transfer images onto sheets of paper or other medium. In a typical image-forming job, the image-forming machine transfers one or more images onto one or more sheets. When multiple images are transferred, the image-forming process usually transfers the images to arrange the output sheets according to the image-forming job. The output sheet sequence typically corresponds to the image input sequence into the image-forming machine. This ordered input and corresponding output avoids the need to reassemble or otherwise compile the sheets.
Many image-forming machines have a marking engine, an inserter, and a finisher. The marking engine transfers images onto the sheets. If required by the image-forming job, the inserter inserts a preprinted or blank sheet into the sheet output from the marking engine. The finisher collects the output sheets to complete the image-forming job or prepare it for subsequent processing operations.
The marking engine usually has image-forming equipment combined with a sheet feeder and an inverter. The sheet feeder provides the selected paper or other medium to the image-forming equipment for transferring an image. In the image-forming equipment, a photoconductor is selectively charged and optically exposed to form an electrostatic latent image on the surface. Toner is deposited onto the photoconductor surface. The toner is charged, thus adhering to the photoconductor surface in areas corresponding to the electrostatic latent image. The toner image is transferred to a sheet of paper or other medium. A fusing station heats the sheet so the toner adheres to the sheet. The photoconductor is refreshed, cleaned to remove residual toner and charge, and is then ready to make another image. The sheet exits the marking engine.
The inverter helps the marking engine make duplex sheetsxe2x80x94where images are transferred onto both sides of a sheet. To form a duplex sheet, a first image is transferred onto one side of a sheet. The sheet is routed through the inverter, which xe2x80x9cinvertsxe2x80x9d or turns the sheet so the opposite side is exposed to the image-forming equipment. The inverter returns the sheet to the image-forming equipment, where a second image is transferred onto the other side of the sheet.
FIG. 5 is a representation of an image-forming job having twelve sheets. Sheet 3 is an inserted sheet and may be preprinted, blank, or the like. The inserted sheet is processed through the inserter. Sheets 1-2 and 4-12 are duplex sheets, where images are transferred onto both sides of a sheet. The duplex sheets are processed on both sides by the marking engine before passing through the inserter into the finisher.
A job ordering system divides the image-forming job into sequential events or frames related to the operation of the image-forming machine. In the frames, the image-forming machine produces output sheets in a sheet sequence corresponding to the order for the image-forming job. Generally, the image-forming job is ordered when it is sent or provided to the image-forming machine.
The job ordering system usually follows criteria based on the mechanical configuration of the image-forming machine. Generally, the back image of a duplex sheet is processed first to avoid having to invert the sheet again. A front image of a duplex sheet is separated from a corresponding back image by a certain number of frames. In one approach, the front image is separated from a corresponding back image by eight frames.
When a duplex sheet is processed, the sheet remains inside the image-forming machine after the first side is processed. The duplex sheet then passes through the inverter. The output for such a frame is an empty space. The image-forming equipment processes the duplex sheet again. Once images are transferred on the back and front sides, the duplex sheet exits the image-forming machine.
FIG. 7 is a representation of a job ordering system for the image-forming job in FIG. 5 according to the prior art. The activities of the marking engine, inverter, inserter, and finisher are summarized for each frame. In the marking engine, images are transferred onto the back sides of duplex sheets 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, and 12 in frames 1, 3, 5, 7, 9, 11, 15, 17, 19, 21, and 23 respectively. Sheets 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, and 12 pass through the inverter after the respective back images are formed. Accordingly, frames 2, 4, 6, 8, 13, 22, 25, 27, 29, and 31 are empty. Images are transferred onto the front sides of sheets 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, and 12 in frames 10, 12, 14, 16, 18, 20, 24, 26, 28, 30, and 32 respectively. After the front images are formed, sheets 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, and 12 exit the marking engine, passing through the inserter to the finisher. As the sheets exit the marking engine, the inserter places the inserted sheet 3 between duplex sheets 2 and 4. The finisher outputs sheets 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 sequentially. This job ordering system takes 32 frames and, in one approach, has a sheet output rate of less than about 55 pages per minute.
In the job ordering system, the skip or empty frames help provide a sheet output corresponding to the sheet sequence of the image-forming job. However, the skip frames increase the process time to complete the image-forming job. The skip frames also increase maintenance of the image-forming equipment. Essentially, the skip frames use the image-forming equipment without transferring images.
Accordingly, a job ordering system is needed for an image-forming machine that uses fewer empty frames and maintains the sheet output in accordance with an image-forming job.
The invention provides a job ordering system for an image-forming machine that transfers an image onto a sheet at essentially the same time in which an inserter places an inserted sheet into a sheet output path. While the image transfer and sheet insertion occur at essentially the same time or within the same frame of an image-forming job, these events occur at different locations in the image-forming machine.
In one aspect, the image-forming machine with a job ordering system has image-forming equipment, a sheet output path, and an inserter. The image-forming equipment transfers an image onto a sheet. The image-forming equipment may transfer one or more images onto a plurality of sheets according to a sheet sequence for an image-forming job. The image-forming job may have one or more frames and one or more inserted sheet positions. The sheet output path receives the sheet from the image-forming machine. The sheet output path may receive a plurality of sheets from the image-forming machine. The inserter places an inserted sheet onto the sheet output path at essentially the same time as the image-forming equipment transfers the image onto the sheet. The inserter may place one or more inserted sheets onto the sheet output path at one or more inserted sheet positions. The image-forming equipment may transfer one or more images onto the plurality of sheets at essentially the same time as the inserter places one or more inserted sheets onto the sheet output path.
The image-forming machine may have a marking engine, an inverter, and a finisher. The image-forming machine may be enclosed inside a housing. The sheet output path may include one or more conveyors in the marking engine, the inverter, and the finisher. The marking engine includes the image-forming equipment and may include a feeder assembly and an inverter. The image-forming equipment may have a photoconductor, a primary charger, an exposure machine, a toning station, a transfer charger, and a fuser station.
In a method for ordering an image-forming job on an image-forming machine, an inserted sheet is placed onto an output sheet path at essentially the same time as an image is transferred onto a sheet. In an alternate method, one or more images are transferred onto a plurality of sheets according to a sheet sequence for an image-forming job. The image-forming job may have one or more frames and one or more inserted sheet positions. One or more inserted sheets are placed on the sheet output path at one or more of the inserted sheet positions. The one or more inserted sheets are placed on the sheet output path at essentially the same time as the one or more images are transferred onto the plurality of sheets.
According to further aspects of the invention, methods and apparatus for ordering an image-forming job on an image-forming machine are provided, comprising transferring at least one image onto a plurality of sheets with interleave duplex according to a sheet sequence for an image-forming job, wherein the image-forming job has at least one inserted sheet position; and placing at least one inserted sheet onto a sheet output path at the at least one inserted sheet position corresponding to an interleave duplex space.
Other systems, methods, features, and advantages of the invention will be or will become apparent to one skilled in the art upon examination of the following figures and detailed description. All such additional systems, methods, features, and advantages are intended to be included within this description, within the scope of the invention, and protected by the accompanying claims.